1. Technical Field
The present invention relates to rehabilitation exercise devices, and more particularly, to an interactive training device, which comprises an operation unit and an interaction unit. In use, a user directly or indirectly operates the operation unit with his/her extremity voluntary movements. Then the operation unit performs motions in response to the movements and converts the motions into particular signals that are later transmitted to the interaction unit. While the interaction unit presents a simulation scene in a display, it receives and processes the signals output by the operation unit and converts the signals into an object moving in the scene corresponding to the motions of the operation unit.
2. Description of Related Art
Among various existing rehabilitation exercise devices operated by users' extremity voluntary movements, those for training users' balance are related to the present invention and will be described as a background of the technology implemented in the present invention.
In U.S. Pat. No. 4,509,743 (hereinafter referred to as '743 patent), a balance training apparatus comprises a base whereon a foot plate is supported by a plurality of springs disposed in a circular arrangement around a center of the foot plate so as to permit tilting of the foot plate relative to the base in all directions. Drive means is also provided for imparting a continuous irregular tilting movement to the foot plate. Thereby an athlete stands on the foot plate receives a balance training upon the tilting of the foot plate.
In U.S. Pat. No. 4,787,630 (hereinafter referred to as '630 patent), an exercise device includes a base assembly and a platform assembly supported by a bearing at a center of the base assembly for being stepped by a user. A semi-cylindrical rocker bar is provided at a bottom of the base assembly for contacting a horizontal physical surface so as to rock back and forth. When a user stands on the platform assembly, he/she can actively conduct a balance training by leaning his/her body in an irregular manner.
While '743 patent implements the active motions of the training apparatus to train a user to keep balance by passively shifting his/her center of body gravity, '630 patent uses a user's voluntary operation to operate the exercise device. However, neither '630 patent nor '743 patent involves a principle of “interactive visual-feedback control”. Thus, users of those prior art devices are allowed of nothing but simply operating the devices, rendering exercise humdrum.
The so-called “interactive visual-feedback control” refers to a series of procedures including connecting an exercise device with an interaction unit, converting motions of the exercise device into particular signals, transmitting the particular signals to the interaction unit, receiving and processing the signals by a suitable software at the interaction unit wherein the software presents a simulation scene on a display for a user's viewing, and processing the signals with the software so as to convert the signals into movements of a dynamic object in the simulation scene, whereby a user can operate the exercise device according to situations shown in the simulation scene. Some prior exercise devices using the technology of “interactive visual-feedback control” will be briefly described below.
U.S. Pat. No. 4,817,950 (hereinafter referred to as '950 patent) provides a surfing simulator. Therein, a surfboard is supported by suspension system for allowing a user to stand thereon and control the same to tilt in all directions. Plural attitude sensors and switch modules are implemented to sense tilt directions and tilt angles of the surfboard. The attitude sensors and switch modules are connected to a computer terminal wherein a terminal display presents a simulated wave scene and a surfing figure controlled by the surfboard, so that a user can operate the surfboard to tilt along expected tilt directions for expected tilt angles for responding to the dynamic wave scene.
U.S. Pat. No. 5,613,690 (hereinafter referred to as '690 patent) relates to a balance training device, comprising a balance platform disposed on a base platform. The balance platform and the base platform are combined through a spherically shaped convex support and a spherically concave depression thereof, which form a low friction interface. The base platform is equipped with plural sensors and switches for sensing tilt directions of the balance platform. The sensors are linked to a personal computer or the like and providing a display of the angular displacement for the user on a computer monitor, through a suitable program.
Since '690 and '950 patents both use sensors and switches to sense the tilt movements of the surfboard or the balance platform, they have common defects due to the plural sensors and switches that complicate hardware structure of the devices and take up substantial space in the devices. Besides, in the aforementioned devices, the sensed data require complex computing processes and thus transmission lag tends to happen. Consequently, real-time reflection of the user's operation to the balance platform or the surfboard in its corresponding simulation scene may be impeded. Besides, while the sensors and switches are both sorts of passive sensing elements, insufficiency in location or in amount thereof can adversely affect the sensitivity and precision of the conventional training devices with respect to the tilt directions and tilt angles of such passive sensing elements.